The colonoscopic vacuum model–simulating biomechanical restrictions to provide a realistic colonoscopy training environment

Abstract

Introduction Practicing endoscopic procedures is fundamental for the education of clinicians and the benefit of patients. Despite a diverse variety of model types, there is no system simulating anatomical restrictions and variations in a flexible and atraumatic way. Our goal was to develop and validate a new modelling approach for adhesion forces between colon and abdominal wall. Methods An inlay for a standard mechanical trainer was designed and 3D printed. Colon specimens were fixed to the inlay along colon ascendens (CA) and colon descendens (CD) by a vacuum. Our system, which we refer to as Colonoscopy Vacuum Model (CoVaMo), was validated with 11 test persons with varying level of expertise. Each performed one colonoscopy and one polypectomy in the CoVaMo and in the Endoscopic Laparoscopic Interdisciplinary Training Entity (ELITE). Achieved adhesion forces, times required to fulfill different tasks endoscopically and a questionnaire, assessing proximity to reality, were recorded. Results Mean adhesion forces of 37 ± 7 N at the CA and 30 ± 15 N at the CD were achieved. Test subjects considered CoVaMo more realistic than ELITE concerning endoscope handling and the overall anatomy. Participants needed statistically significantly more time to maneuver from anus to flexura sinistra in CoVaMo (377 s ± 244 s) than in ELITE (58 s ± 49 s). Conclusion We developed a training environment enabling anatomically and procedural realistic colonoscopy training requiring participants to handle all endoscope features in parallel. Fixation forces compare to forces needed to tear pig colon off the mesentery. Workflow and inlay can be adapted to any arbitrary ex vivo simulator.

Not All Porcine Intestinal Segments Are Equal in Terms of Breaking Force, but None Were Associated to Allometric Parameters

“…Modelling the biomechanics of the living organism is crucial for the acceptance of ex vivo simulators [35]. They have been evaluated and thoroughly tested, including a randomized controlled trial, and found to be helpful in gaining experience, training, and even proficiency, irrespective of the level of experience at the start of the training [32,78].…”

“…Such a training opportunity contributes towards better training and aid in gaining experience that is required to adequately perform difficult tasks within a procedure [31]. Porcine-based endoscopy simulators have been created for endoscopic submucosal dissection [32], peroral endoscopic myectomy [33], anastomotic strictures in Crohn's disease [34], and colonoscopy [35]. Successful use of these simulators, however, requires that they adequately model the human patient and be consistent models, i.e., in a way that they always have similar tissue parameters and tissue properties.…”